Regenerative devices



June 2, 1964 SMITH 3,135,215

REGENERATIVE DEVICES Filed March 5, 1963 3 Sheets-Sheet 1 June 2, 1964L. F. SMITH 3,135,215

REGENERATIVE DEVICES Filed March 5, 1963 3 Sheets-Sheet 2 June 2, 19641.. F. SMITH 3, ,2 5

REGENERATIVE DEVICES Filed March 5, 19 3 Sheets-Sheet :5

9 30G J 3o Is r 2 I2 "12 l2 3| 28 a u is g 20 H a 29 I I 3 I" I4 I I M:n 3e I I -a K 4 '6 t F l G. 6. I I j\\ GAS BEARINGS x I GAS BEARINGS /H1" 1" r' I United States Patent 3,135,215 REGENERATIVE DEVICES Lewis F.Smith, Schenectady, N.Y., assignor to Mechanical TechnologyIncorporated, Latham, N.Y., a corporation of New York Filed Mar. 5,1963, Ser. No. 262,881 12 Claims. (Cl. 103-87) This invention relates toregenerative devices which may be used as fans, pumps, turbines andregenerative compressors. Prior devices of this type have been quitecumbersome, bulky, and formed of a relatively large number of differentparts which make such devices un duly expensive.

An object of this invention is to provide a device of this type which isregenerative, may be made of a minimum number of different parts to keepthe cost to a minimum, which will have a minimum height, Width andoverall length, with which the direction of flow through it may bereversed by reversing the direction of rotation of its rotor, with whichthe sections of each of its casings may be molded or cast in simplemolds, with which its parts may be rearranged and modified in simplemanners to operate selectively in series or parallel, which will requirea minimum of operating power, and which will be relatively simple,practical, efficient, durable, compact and inexpensive.

Other objects and advantages will appear from the following descriptionof several embodiments of the invention, and the novel features will bepointed out in connection with the appended claims.

'In the accompanying drawings:

FIG. 1 is a half sectional elevation of a regenerative compressorconstructed in accordance with this invention and' arranged as a twostage compressor, the section being taken approximately along the lineD--D of FIG. 2;

FIG. 2 is a partial sectional elevation of one section of one of thecasings, as viewed approximately along the line 2--2 of FIG. 1;

FIG. 3 is a partial sectional elevation of part of one of the casingsand the impellers; the section being taken approximately along theline'3-3 of FIG. 1;

FIG. 4 is a plan of part of a casing section as shown in FIG. 2 andviewed from the line 44 of FIG. 2;

FIG. 5 is a view similar to FIG. 1 but with the casing sectionsrearranged for parallel operation;

FIG. 6 is a longitudinal, sectional elevation of another embodiment ofthe invention, with the casing sections arranged for two stage, seriesoperation; and FIG. 7 is a view similar to FIG. 6, but illustrating theuse therein of gas radial and thrust bearings.

In the embodiment of the invention illustrated in FIGS. 1-4, a pair ofannular casings 1 and 2' are disposed in aligned end to end abutting andsealing relation to one another, and a motor housing 3 abuts and isdisposed in sealing contact against one exposed end face of the pair ofabutting casings, with a rotor or shaft 4 of the motor extending axiallyintoand along the cylindrical space 5 that is encircled by the casings 1and 2. A plate 6 is disposed insealing contact against the other exposedend face of the pair of abutting casings, and extends across and closesthe adjacent end of the space 5. Bolts 5A pass through apertures 5B inthe plate 6 and corresponding passages in the casings to clamp them alltogether as a unit. Each casing 1 and 2 has an annular chamber 7 withinit that opens into the space 5 through an annular slot 8 in the innerperipheral wall of the casing. A pair of discs 9 and 10 are fixedcentrally of themselves on the shaft or rotor 4 in space 5 by spacers 11also fixed on the rotor or shaft so as to rotate with the shaft orrotor. These discs 9 and 10- are spaced apart axially along the shaft orrotor as shown, with their marginal portions extending, with closeclearances, through the annular slots 8 aligned therewith into theannular chambers 7 and there they carry a plurality of impeller vanes 12that are spaced apart in a circular row along the peripheral portion ofthe discs and have radial impeller walls or faces that extend sidewisefrom the discs.

The casing 1 has a port 13 opening through its outer peripheral wallinto its said annular chamber 7 and another port 14 opening through itsinner peripheral wall from its chamber 7 into the space 5. The casing 2has similar ports 15 and 16 in its outer and inner peripheral wallsrespectively. The annular chamber in each casing has a short portion 17along it of restricted crosswise and radial dimensions, with which theimpeller vanes have close clearance to create a stripper or stripperportion, and

the ports 13 and 14 of casing 1 are located closely adjacent to the endsof the stripper portion in the annular chamber of casing 1, and theports 15 and 16 of casing 2 are similarly located closely adjacent tothe ends of the stripper portion in the annular chamber of casing 2. Theannular chamber of each casing'in the longer annular distance betweenthe ends of the stripper portion has the usual or any suitableregenerative clearance which is of greater crosswise and radialdimensions from the vanes than for the stripper portion, as usual inregenerative compressors. The face area of each disc 9 and 10,

which is within the pace..5 between the spacers 11 and the casings 1 and2, is apertured from face to face such as by a plurality of apertures18A (FIG. 3), arranged in spaced apart relation to one another.

Each casing 1 and 2, is formed of two sections 18 and 19 which abut faceto face in sealing contact along the line 20 and the slot 8, and thesections 18 and 19 of each casing have in their abutting facescomplementary recesses 21 and 22 respectively, which together form theannular chamber of each casing. To reduce the number of stock partsnecessary, the sections 18 and 19 of each casing have theircomplementary recesses 21 and 22 mirror duplicates or images of oneanother, that is, identical of shape and size if the recess of one isviewed in a mirror and compared with the other. In the embodimentillustrated in FIG. 1, the part 19 of casing 2 abuts the part 19 ofcasing 1, which makes the vanes in the two casings propel a gas passingthrough it in opposite radial directions while the vanes which are fixedon the shaft 4 move in the same circular directions in both casings 1and 2.

The device as shown in FIGS. 12 is arranged for series operation, suchas a two stage gas compressor. The gas to be compressed is supplied tothe inlet port 13 of easing 1 and removed from outlet port 15 of easing2. When the motor in the housing 3 is operated, it will rotate the shaft4 in the direction shown by the arrow in FIG. 2, and it will in turnrotate in the same direction both of the discs 9 and 10 which are fixedon the shaft 4 by spacers 11. The gas will enter the annular chamber ofcasing 1 at the left end of the stripper area 17 in FIG. 2 and be forcedby the vanes to the other end of the stripper area and there dischargeit through port 14 into the space 5. This gas may pass through apertures18 in the disc 9 when necessary to move to the casing 2 and there itpasses through the inlet port 16 of casing 2 in the annular chamber ofcasing 2, some of the gas passing through apertures 18 in the disc 10when necessary. In the annular chamber of casing 2, the gas is forcedfrom one end to the other of the stripper area in casing 2, in thenonrrestrictive portion, and there expelled through the port under a twostage compression. Each annular chamber, in the portion thereof betweenthe ends of the stripper area, have shapes and sizes that provide forregenerative compression, and for that purpose the clearance of thechamber walls with the edges of the vanes will be designed according tothe usual engineering practice to provide the desired regenerationduring the compression.

In the example of the invention shown in FIG. 5, the parts are of thesame construction as in FIG. 1, except that the closure, plate 6, whichis unapertured across the space 5, is replaced with a plate 6A which hasan aperture 26 and a tubular projection 27 aligned and communicatingwith the aperture 26, through which a gas to be compressed may enter thespace 5. Also, the casing 2 is reversed in its face to face relationwith the casing 1 and the section 18 of casing 2, whose recess isidentical with that of section 18 of casing 1, is now directly abuttingand sealed against the section 19 of casing 1, so that the relativearrangements of the sections will be the same in both casings 1 and 2and not reversed in respect to one another as they were in FIG. 1. Withthis rearrangement of the sections of easing 2, and the replacement ofplate 6 with plate 6A, the device is set for parallel compression inwhich the flow capacity of the device is approximately doubled, but onlyoperates in one stage of compression when the motor in housing 3 isoperated, the shaft 4 and discs 9 and 10 will be rotated. Gas to becompressed is supplied, through tubular projection 27 and aperture 26 ofplate 6A, into space 5, and some of this supplied gas will pass throughthe apertures 18A of the discs 9 and 10 in order that the gas can reachall inlets to the annular chambers of casings 1 and 2. The inner ports14 and 16 now function as both inlet ports that pass gas from space 5into the annular chambers 7 of both casings 1 and 2. The outer ports 13and 15 now both function as outlet ports and deliver the gas compressedin both annular chambers into a common duct, not shown, or to differentducts for delivery to diiferent receiving apparatus, as may be desired.

In the embodiment of the invention illustrated in FIGS. 6 and 7, thecasings 1 and 2 directly abut in sealing end to end contact with oneanother in the same section arrangement as explained in connection withFIGS. l-4, and plates 28 and 29 abut against and are secured by screws29a to the exposed end faces of the assembled casings 1 and 2. Bolts 30pass through aligned passages 30a in the margins of the casings 1 and 2to detachably couple them together in a complete unit. The plates 28 and29 at their centers are bulged outwardly to increase the axial length ofthe space 5 which is encircled by the casings 1 and 2, and provide fordisposition of the operating motor 31 centrally within the space 5. Inthis embodiment the shaft 4 and its motor that were provided in FIGS. 1and 2, are replaced by this motor 31 which has a rotor 32 and a. stator33. The stator 33 is cylindrical in shape and fixed centrally of itselfon a stationary shaft 34 that extends between, and at its ends isdetachably mounted in, the end plates 28 and 29. One end of thisstationary shaft 34 has a passage 35 leading to the stator from the freeend of the shaft, which passage 35 is aligned at such free end with acentral aperture 36 in the plate 29. Through this passage 35 andaperture 36, conductor wires 37 may be disposed to connect a source ofelectric current (not shown) to the windings of the stator for causingrotation of the rotor.

The rotor 32 is secured by screws 38 to the inside of a tubular shell39, which at its ends is rotatably supported by ball bearings 40 on theend portions of the fixed shaft 34. Fixed centrally of themselves on theexterior periphery of the shell 39 are two discs 41 and 42 whichcorrespond in function to the discs 9 and 10 of FIG. 1, and are spacedfrom one another lengthwise along the shell 39. The outer marginalportions of the discs 41 and 42 extend through the slots 8 into' theannular chambers of the casings 1 and 2 respectively, as in FIGS. 1 and5, and within the casing chambers they carry a peripheral row ofimpeller vanes 12 as in FIGS. 1 and 5. The discs 41 and 42 and the vanes12 are preferably formed of discsof sheet material, usually sheet metal.Each disc 41 and 42, in its portion exposed in space 5, is provided witha plurality of apertures 43 (FIGS. 6 and 7) from face to face so thatany gases in the space 5 may pass through the apertures 43 in bothdiscs, and in both directions.

Each casing 1 and 2 is formed as explained and illustrated in connectionwith FIGS. 14 with a stripper area 17, a port 13 or 15 through the outerperipheral casing wall into the annular chamber, and another port 15 or16 from the annular chamber through the inner peripheral wall of thecasing into the space 5. In FIGS. 6 and 7, the casing sections arearranged in the same order as in FIGS. 1 and 2, for series operation,that is, as a two stage compressor, but if they are to be arranged inthe order shown in FIG. 5 for parallel operation, one of the end platesshould be provided with an aperture and tubular inlet, like 26 and 27respectively of FIG. 5. With the arrangement of the casing sections asshown in FIGS. 6 and 7, the operation will be similar to that explainedfor FIGS. 1 and 2, the gas going in through an inlet port 13 (FIG. 6) ofthe casing 1, then expelled under pressure through outlet port 15 intospace 5, then into the annular chamber of easing 2 through the port 16and expelled under further pressure by port 15 of casing 2. Suitableconduit connections, not shown, are made to the exterior ports ofcasings 1 and 2 to direct gas to be compressed into the compressor andto receive and conduct away the gas from casing 2 under the two stagecompression.

Referring next to FIG. 7, the construction is the same as explained forFIG. 6 except that instead of the ball bearings 40 of FIG. 6, a suitablegas bearing is provided between the outer periphery of the stator andthe inner periphery of the rotor. Gas bearings are well known and hence,are not shown. Also, gas thrust bearings are provided at opposite sidesof each slot 8 of each casing 1 and 2 where the discs enter into theannular chambers, acting between the slot walls and the discs.

The sections 18 and 19 of each casing 1 and 2 are easily and accuratelymolded, with their recesses being mirror duplicates of one another, byany of the available molding methods, including injection molding anddie casting. Cores for the molding or casting may be used to provide forthe parts of the ports in each section leading to each annular chamber,but preferably each section 18 and 19 is cut away as shown by the dottedline 44 (FIG. 1) at each inner port, so that the inner port half in eachsection of the casing opens into the annular slot 8 which makes the useof cores to form the inner ports unnecessary. The outer ports are formedhalf in each section of a casing and meeting one another at the abuttingfaces of the sections of eachcasing. It will be observed that by makingthe sections of each casing mirror duplicates of one another, only twodies are required to mold or cast both sections for each casing, whichgreatly reduces the cost of manufacture, and by selective arrangement ofthe sections in their abutting relation, the device can be set up forseries or parallel operation. The device is exceptionally eflicient forthe compression of gases and can function as a pump either one or twostages, and if gases are forced through this device, the discs will berotated, and if the motor is replaced by an electric generator, thisrotation of the motor shaft, or rotor in FIG. 6, will cause generationof current. This device would thus operate as a turbine drivengenerator. If air or gases are forced through one of the casings, therotor will turn and operate the shaft, and hence, function as a turbine.When the direction of flow of gas through the casings is reversed, thediscs will rotate in the opposite direction. The overall dimensions ofthe device for a selected capacity are relatively small and hence, thedevice is very compact. It is made of a minimum number of difierentparts, the parts are relatively simple and inexpensive, and the deviceis very eflicient. The casings may be rearranged and modified in simpleselected manners to serve different functions.

In FIG. 6, the motor disposed as shown reduces the volume of the packageby using more efficiently the hub space and thereby reduces the overalllength. This is true whether rolling or gas bearings are used. In FIG. 7the volume of the package is reduced to a minimum by utilizing the motorgap as the gas bearing space for the radial bearing. The gas bearingsgive long life and require minimum power. In fans, most of which havelow horsepower, the bearing loss is an appreciable portion of the powerloss and gas bearings reduce this power loss.

Devices of the type herein disclosed as arranged for series operationdevelop more than twice the pressure of a single stage centrifugalcompressor at the same tip speed. By making inlet and outlet ports,stripper section and impeller vanes completely symmetrical about aradial plane through the center of rotation, the flow direction can bereversed by reversing the direction of rotation of the vanes, andidentical pressure rise versus flow characteristics results. The uniqueuse of inlet and outlet ports in the inner and outer peripheries of thecasings, allows more efficient use of the full periphery for generatingpressure rise.

It will be understood that various changes in the details, materials andarrangements of parts, which have been herein described and illustratedin order to explain the nature of the invention, may be made by thoseskilled in the art within the principle and scope of the invention asexpressed in the appended claims.

I claim:

1. A regenerative device for use as a fan, turbine pump, compressor andthe like comprising:

(a) a rotating disc support member,

(b) a pair of identical parallel, spaced discs mounted for rotation onsaid disc support member,

() an annular impeller section on said discs including vanes extendingradially outward from either side of the marginal area of said discs,

(d) said vanes having like configuration,

(e) a pair of identical abutting annular casings each housing one ofsaid discs,

(1) each of said casings including a pair of disc housing members,

(g) each disc housing member in a pair having its inside face the exactopposite of the inside face of the other disc housing member in saidpair and abutting said other member in face to face contact,

(h) said casings forming with said supporting disc member a centralannular chamber about said supporting disc member,

(i) each disc housing member including an annular internal flange and anannular external flange,

(j) each pair of disc housing members having their external flanges inaligned abutting face to face relationship and their internal flanges inaligned spaced relationship,

(k) each pair of said disc housing members forming an annular recessbetween said flanges,

(I) each of said discs extending from said disc member support throughsaid central annular chamber and between the internal flanges of a pairof said disc housing members and spaced slightly from said internalflanges and projecting into said annular recess,

(m) said discs having their impeller section lying Wholly within saidannular recess and spaced from the walls thereof,

(n) the cross-sectional area of said impeller section being slightlyless than the minimum cross-sectional area of said annular recess,

(0) said annular recess including a short restricted area slightlygreater in cross-section than the cross-sectional area of said impellersection,

(p) said annular recess including an enlarged arcuate chamber extendingfrom one side of said restricted area to the other side of saidrestricted area,

(q) each casing having an inlet port adjacent one side of saidrestricted area leading from outside said casing into said arcuatechamber and a pair of ports on either side of said impeller sectionadjacent the other side of said restricted area and extending from saidarcuate chamber into said central annular chamber,

(r) said discs having in the region of said central a11- nular chamberfluid transfer ports to permit fluid flow to either side of saidimpellers,

(s) said casings in said regenerative device being reversible to twooperable positions, one for directing fluid flow in a clockwisedirection when in its first position and in a counterclockwise directionwhen in its second position,

(t) and means for controlling and directing flow of fluid within saidcentral chamber.

2. A regenerative device as in claim 1 and wherein:

(a) said casings are mounted in reverse order with respect to each otherfor series operation.

3. A regenerative device as in claim 1 and wherein:

(a) said casings are mounted in similar order with respect to each otherfor parallel operation.

4. A regenerative device as in claim 1 and wherein:

(a) said means for controlling and directing flow of fluid within saidcentral chamber includes a pair of housing plates,

(b) said housing plates being spaced from each other the distance ofsaid annular central chamber and defining with said disc support memberand said supporting disc members said annular central chamber.

5. A regenerative device as in claim 4, and wherein:

(a) one of said housing plates includes a fluid passageway therethrough.

6. A regenerative device as in claim 1 and wherein: (a) said casings aremounted in similar order with respect to each other for paralleloperation, and (b) wherein said means for controlling and directing flowof fluid within said central chamber includes a pair of housing plates,

(0) said housing plates being spaced from each other the distance ofsaid annular central chamber and defining with said disc support memberand said supporting disc members said annular central chamber, and

(d) one of said housing plates including a fluid intake passagewaytherethrough.

7. A regenerative device as in claim 1, and wherein:

(a) said means for controlling and directing flow of fluid within saidcentral chamber includes a pair of housing plates,

(b) said housing plates supporting a motor mechanism for driving saiddisc support member.

8. A regenerative device as in claim 1 and wherein:

(a) said means for controlling and directing flow of fluid within saidcentral chamber includes a pair of housing plates,

(b) said housing plates supporting a motor mechanism for driving saiddisc support member,

(0) said motor mechanism being positioned between and within the areabetween said plates.

9. A regenerative device as in claim 8 and wherein:

(a) said device includes air bearings for said discs and said discsupport member.

10. A regenerative device as in claim 1 and wherein:

(a) said discs are thin plates having a flat continuous planar surfaceon either side thereof.

11. A regenerative device as in claim 1 and wherein:

(a) said pair of ports on either side of said impeller of each casinglie directly beneath said arcuate chamber and lie within the areabounded by said arcuate chamber.

12. A regenerative device as in claim 1 and wherein:

(a) said inlet port and said pair of ports of each casing are spacedapart along the linear length of said annular recess an angular distanceless than 180.

References Cited in the file of this patent UNITED STATES PATENTS KaneFeb. 13, Claypool Sept. 6, Hollander Nov. 6, Abrarnson Oct. 6,Wislicenus June 24, Font Apr. 17, Perry Dec. 2, Anderson Dec. 16,

FOREIGN PATENTS France Mar. 13,

1. A REGENERATIVE DEVICE FOR USE AS A FAN, TURBINE PUMP, COMPRESSOR ANDTHE LIKE COMPRISING: (A) A ROTATING DISC SUPPORT MEMBER, (B) A PAIR OFIDENTICAL PARALLEL, SPACED DISCS MOUNTED FOR ROTATION ON SAID DISCSUPPORT MEMBER, (C) AN ANNULAR IMPELLER SECTION ON SAID DISCS INCLUDINGVANES EXTENDING RADIALLY OUTWARD FROM EITHER SIDE OF THE MARGINAL AREAOF SAID DISCS, (D) SAID VANES HAVING LIKE CONFIGURATION, (E) A PAIR OFIDENTICAL ABUTTING ANNULAR CASINGS EACH HOUSING ONE OF SAID DISCS, (F)EACH OF SAID CASINGS INCLUDING A PAIR OF DISC HOUSING MEMBERS, (G) EACHDISC HOUSING MEMBER IN A PAIR HAVING ITS INSIDE FACE THE EXACT OPPOSITEOF THE INSIDE FACE OF THE OTHER DISC HOUSING MEMBER IN SAID PAIR ANDABUTTING SAID OTHER MEMBER IN FACE TO FACE CONTACT, (H) SAID CASINGSFORMING WITH SAID SUPPORTING DISC MEMBER A CENTRAL ANNULAR CHAMBER ABOUTSAID SUPPORTING DISC MEMBER, (I) EACH DISC HOUSING MEMBER INCLUDING ANANNULAR INTERNAL FLANGE AND AN ANNULAR EXTERNAL FLANGE, (J) EACH PAIR OFDISC HOUSING MEMBERS HAVING THEIR EXTERNAL FLANGES IN ALIGNED ABUTTINGFACE TO FACE RELATIONSHIP AND THEIR INTERNAL FLANGES IN ALIGNED SPACEDRELATIONSHIP, (K) EACH PAIR OF SAID DISC HOUSING MEMBERS FORMING ANANNULAR RECESS BETWEEN SAID FLANGES, (L) EACH OF SAID DISCS EXTENDINGFROM SAID DISC MEMBER SUPPORT THROUGH SAID CENTRAL ANNULAR CHAMBER ANDBETWEEN THE INTERNAL FLANGES OF A PAIR OF SAID DISC HOUSING MEMBERS ANDSPACED SLIGHTLY FROM SAID INTERNAL FLANGES AND PROJECTING INTO SAIDANNULAR RECESS, (M) SAID DISCS HAVING THEIR IMPELLER SECTION LYINGWHOLLY WITHIN SAID ANNULAR RECESS AND SPACED FROM THE WALLS THEREOF, (N)THE CROSS-SECTIONAL AREA OF SAID IMPELLER SECTION BEING SLIGHTLY LESSTHAN THE MINIMUM CROSS-SECTIONAL AREA OF SAID ANNULAR RECESS, (O) SAIDANNULAR RECESS INCLUDING A SHORT RESTRICTED AREA SLIGHTLY GREATER INCROSS-SECTION THAN THE CROSS-SECTIONAL AREA OF SAID IMPELLER SECTION,(P) SAID ANNULAR RECESS INCLUDING AN ENLARGED ARCUATE CHAMBER EXTENDINGFROM ONE SIDE OF SAID RESTRICTED AREA TO THE OTHER SIDE OF SAIDRESTRICTED AREA, (Q) EACH CASING HAVING AN INLET PORT ADJACENT ONE SIDEOF SAID RESTRICTED AREA LEADING FROM OUTSIDE SAID CASING INTO SAIDARCUATE CHAMBER AND A PAIR OF PORTS ON EITHER SIDE OF SAID IMPELLERSECTION ADJACENT THE OTHER SIDE OF SAID RESTRICTED AREA AND EXTENDINGFROM SAID ARCUATE CHAMBER INTO SAID CENTRAL ANNULAR CHAMBER, (R) SAIDDISCS HAVING IN THE REGION OF SAID CENTRAL ANNULAR CHAMBER FLUIDTRANSFER PORTS TO PERMIT FLUID FLOW TO EITHER SIDE OF SAID IMPELLERS,(S) SAID CASINGS IN SAID REGENERATIVE DEVICE BEING REVERSIBLE TO TWOOPERABLE POSITIONS, ONE FOR DIRECTING FLUID FLOW IN A CLOCKWISEDIRECTION WHEN IN ITS FIRST POSITION AND IN A COUNTERCLOCKWISE DIRECTIONWHEN IN ITS SECOND POSITION, (T) AND MEANS FOR CONTROLLING AND DIRECTINGFLOW OF FLUID WITHIN SAID CENTRAL CHAMBER.